Unmanned aerial vehicles (UAVs), commonly known as drones, are aircrafts without a human pilots on board. Over the past few decades, there has been significant research and development of UAVs, particularly with multi-rotor based UAVs. This has led to entirely new commercial markets for multi-rotor UAVs for a wide range of commercial applications beyond recreational/hobby use, including industrial surveying, construction, mining, stockpiling, photogrammetry, aerial photography, cinematography and video, live streaming, newsgathering, multispectral analysis for vegetation, security and surveillance, asset inspection, transmission and pipeline inspection. It is very likely that in future, and with further development of multi-rotor UAVs, new commercial uses will emerge.
Despite this rapidly growing industry for multi-rotor UAV technology and the promise it holds, there still remains some important obstacles which need to be better addressed. In particular, safety to people and property remains of utmost importance.
For instance, high winds, malfunction or one or more rotors, shaking, loss of communication with the automation control or battery failure may lead to situations where the UAV loses control and may crash-land, often at an uncontrolled descent. This poses a significant risk to people and property who may be positioned under the UAV.
This is a major concern for governmental agencies, which in the USA has led to substantial regulations at the Federal Aviation Administration (FAA) around control and use of UAVs under 55 pounds (24 kg). In early 2015, restrictions imposed on use users include weight restrictions, allowed hours of flight, visual line of sight operation, height restrictions, operator certification, aircraft registration and so forth.
Beyond safety concerns, highly sophisticated UAV systems are now being developed for important commercial operations, and the technology in the UAV hardware and/or its payload can often be very valuable. It will be important to develop systems to avoid damage to this technology during an uncontrolled crash-landing. In order to alleviate these risks and to enable viable commercial use of these UAVs on a large scale, further safety measures are in urgent need.
One mechanism which has been investigated in recent years to address these safety concerns is to mount a parachute system onto multi-rotor UAVs. Then, if the UAV or user loses control, a manual or automated parachute system could deploy a parachute to allow a controlled or semi-controlled descent of the UAV to avoid injury to people, property and/or the UAV itself.
Yet, the products that have been developed thus far have been problematic with regard to at least one of: slow deployment time; slow parachute catch once deployed; requires explosives or spring systems for deployment, or complicated power systems; non-automation; addition of significant weight to the UAV which becomes a burden on flight time; non-reliability due to false triggers; unintentional exhaustion of the firing mechanism before use; and/or component(s) and/or system not being re-usable.
At least some embodiments of the teachings detailed herein address the foregoing problems or at least to provide the public with a useful choice.
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
Throughout this specification, the word “comprise”, or variations thereof such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
Further aspects and some utilitarian features of the present disclosure will become apparent from the ensuing description which is given by way of example only.